This belongs to the group of medicines known as phosphodiesterase type 5 inhibitors.

Viagra is used to treat erectile dysfunction. Erectile dysfunction is the inability to achieve or maintain an erection long enough to perform sexual intercourse.

Viagra relaxes the blood vessels in the penis, allowing more blood to enter to achieve an erection.

Before Taking Viagra

Before taking Viagra make sure your doctor or pharmacist knows:

• if you are taking medicine called nitrates for various heart conditions
  
• if you suffer from or have ever suffered from sickle cell anaemia, multiple myeloma or leukaemia
  
• if you suffer from liver, kidney or heart problems
  
• if you have recently had a stroke or a heart attack
  
• if you suffer from low blood pressure or have a bleeding disorder
  
• if you have a stomach ulcer or if you have ever suffered an ulcer
  
• if you have any disease, injury or deformity of your penis
  
• if you suffer from any condition affecting the eye or if there is a family history of eye problems
  
• if you have ever had an allergic reaction to this or any other medicine
  
• if you are taking any other medicines, including those available to buy without a prescription, herbal and complementary medicines
  
• if you are using any other products to treat erectile dysfunction
  
  

How to Take Viagra

Take your medication exactly as directed by your doctor.

You must follow the printed instructions you have been given with your medication.

Viagra should be taken one hour before sexual activity.

Viagra works better on an empty stomach, if taken with or just after food it will take longer to work.

Never take more than the prescribed dose. If you suspect that you or someone else has taken an overdose of Viagra contact your doctor or go to the accident and emergency department of your local hospital at once. Always take the container with you, if possible, even if empty.

This medicine is for you. Never give it to others even if their condition appears to be the same as yours.

Getting the most from your treatment

Before taking any 'over-the-counter' medicines, check with your pharmacist which medicines are safe for you to take alongside Viagra.

You should not take more than one dose in any twenty four hour period.

Do not drink grapefruit juice while taking Viagra.

Viagra may cause dizziness and visual disturbances. Make sure your reactions and sight are normal before driving operating machinery or doing other jobs which could be dangerous, if you were not fully alert.

Side Effects

Along with their useful effects, all medicines can cause unwanted side effects. Speak with your doctor if any of the following side effects continue or become troublesome.

Indigestion, headache, flushing, dizziness, visual problems or painful, red eyes, a skin rash, palpitations (being aware of your heart beat), nasal congestion or a painful erection with no sexual desire.

Note: if you have a persistent erection for four hours or more, contact your doctor at once.

Important: If you experience chest pains, an irregular heartbeat or a sudden sharp headache with numbness or tingling on one side of the body contact your doctor or seek medical attention as soon as possible.

If you experience any other worrying symptoms, which you think may be due to this medicine, discuss them with your doctor or pharmacist.

How to store Viagra

• Keep all medicines out of the reach of children.
  
• Store in a cool dry place, away from direct heat and light.
  
• Never keep out of date or unwanted medicines. Discard them safely out of the reach of children or take them to your local pharmacist who will dispose of them for you.